|
|
|
Forages & Grains
Volume 57 Number 9 Date 06/07/2012 ALFALFA WEEVIL - Larval populations in the southern half of the state have been reduced to less than 1.3 per sweep by pupation and harvesting of alfalfa. The threat from this early-season pest is expected to subside by mid-June. POTATO LEAFHOPPER - Counts in alfalfa remain moderate in most fields and high at a few sites. Surveys in Columbia, Dane, Grant, Green, Iowa, La Crosse and Lafayette counties found 0.3-2.1 per sweep, with an average of 0.9 per sweep. Individual fields in Grant County had populations sufficient to justify treatment (> 2.0 per sweep). Nymphs were collected in about 10% of alfalfa fields checked as of June 6 and populations appear to be increasing. PEA APHID - This insect is still fairly numerous in alfalfa. Counts in the second crop presently range from 2-17 per sweep in the east-central, west-central and southern counties. Winged forms comprise a larger percentage of the population than previously. MEADOW SPITTLEBUG - The adult stage of this insect has become commonplace in Wisconsin alfalfa, signaling that the population has matured and spittle masses should not reappear until next spring. The highest number collected from second crop alfalfa in the past week was 3 per sweep. --Krista Hamilton, DATCP Entomologist 
|
|